Both are able to store much more high-quality data, important for high definition images and high fidelity audio, and both use a blue laser to read information.

Used in games consoles, the two formats offer detailed graphics and stunning sound on one disc.

However, the launch of the rival technologies has split the industries they serve.

Toshiba, with NEC, Sanyo and others, is pushing HD DVD; while backers of Sony's Blu-ray discs include Samsung, Dell and Apple.

In Hollywood, companies like Disney and 20th Century Fox have sided with Sony, while the supporters of HD DVD include Universal. Warner Bros, the company behind the hybrid discs, has said it will support both.